How to install Ruby on Rails in Ubuntu 12.04 LTS

Ubuntu 12.04 LTS (Long Term Support) – Precise Pangolin has already released, and you might have upgraded from 11.10 or installed Ubuntu 12.04 LTS. In this post you will learn how to setup Ruby on Rails on a newly installed Ubuntu 12.04 LTS.

Ruby on Rails is a very popular web development framework, it is based on the principle of “Convention over Configuration”. Although, application development using Rails is quite easy and fun but setting up rails development environment may be difficult and frustrating, specifically for beginners. I had already written a post about setting up rails on Ubuntu 11.10 but few things has changed and need to be updated for the new version of Rails, Ruby and Ubuntu.

“Hassle Free” Rails Installer for Ubuntu 12.04

Although I’ve explained the installation steps in detail but if already know how these things work then better save time by running the script – that will install Ruby on Rails on Ubuntu 12.04 along with the dependencies and RVM.

First change some settings in Gnome Terminal. Go to Edit -> Profile Preferences -> Title and Command and check the “Run Command as login shell” box.

Then make the script executable and execute it (you may have to enter the login password once) –

sudo chmod +x rails-installer.sh
./rails-installer.sh

If anything goes wrong then let me know through comments.

Step by Step Instruction for Setting Up Rails on Ubuntu 12.04 LTS

Just follow these simple steps and withing a couple of minutes you would be creating some nice applications (and of course using Rails).

step 1. Install git and cURL

First of all, update your package repository.

sudo apt-get update

git is a simple, fast and efficient version control system. It is easy to learn, so even if you don’t have any experience with git you can try it in your next rails project (or any other project). you will love it.

sudo apt-get install git

Curl is a simple command line utility for getting file over web protocols, based on libcurl. To install curl simply execute –

sudo apt-get install curl

step 2. Install RVM and Dependencies

RVM is not strictly required but it makes ruby management a lot easier. You can try different implementations of ruby, different versions of ruby and all without any pain. So it’s strongly recommended. but RVM requires the command to be executed as login shell, so open a terminal and go to Edit -> Profile Preferences -> Title and Command and check the box that says “Run Command as a login shell“. (look at the above snapshot)

Installing Javascript Runtime
In newer version of Rails, you also need a Javascript runtime. Although you could install it from the package repository but it’s very outdated. So I recommend installing it using the PPA. (and I’ll also update the script)

step 3. Install Ruby

Now, you got RVM running, installing and running multiple versions or just one version of Ruby is very simple. To install Ruby just pass the version number to rvm install command (or some other implementation of ruby if you want; RVM also supports rbx, ree, JRuby, IRonRuby other than the default MRI) –

rvm install 1.9.3

Then select the Ruby version you want to use, (or make it default so that you don’t have to select it again in new session)

rvm use 1.9.3 --default

Now, you can check the version of ruby, you’re running right now-

ruby -v

step 4. Install Rails

RVM installs ruby as well as the gem utility (managing ruby libraries). To install rails, simply install it using the gem. It will automatically install the latest version unless you specify the version explicitly.